Defensive publication



an has DEFENSIVE PUBLICATION UNITED STATES PATENT OFFICE Published atthe request of the applicant or owner in accordance with the Notice ofApr. 11, 1968, 849 O.G. 1221. Identification is by serial number of theapplication and the heading indicates the number of pages ofspecification, including claims, and of sheets of drawing contained inthe application as originally filed. The file of this application isavailable to the public for inspection; reproduction may be purchasedfor r30 cents per sheet.

Applications published under the Defensive Publication Program have notbeen examined as to the merits of alleged invention. The Patent Oflicemakes no assertion as to the novelty of the disclosed subject matter.

PUBLISHED MARCH 25, 1969 2 Class 560-53 No Drawing. 19 PagesSpecification An oxymethylene copolymer containing 80-99.'5% molar ofoxymethylene units and 0.1 to 20% of units -RO derived from phenols.Preferred phenols have the formula OH Y I H wherein X is halogen ornitro and Y is hydrogen, halogen or nitro. The polymers are made bypolymerizing at least one mole of a cyclic oligomer of formaldehyde,e.g. trioxane with the corresponding phenol with a catalyst suitable forpolymerizing trioxane.

